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Abstract:

This invention is a greatly simplified device for transforming the energy
of water waves into useable energy. The invention is a device for
transforming the energy of water waves into useable energy comprising two
or more buoys or buoys, and structural members connecting buoys, whereby
motions of buoys relative to one another generates torque, and a means
for transferring torque to one or more generators, and a means by which
to enable all generator currents to flow in a single beneficial
direction. Novel systems for interconnecting such devices are also
described herein.

Claims:

1. A device for transforming the energy of water waves into useable
energy comprising two or more buoys, and structural members connecting
said buoys, at least two hinge points, whereby motions of said buoys
relative to one another generates torque, one or more shafts or other
means by which to transfer torque connected to one or more generators,
and a means by which to ensure that one or more generator output currents
flow in a single useful direction despite the reversing of generator
rotation.

2. The device of claim 1 with one or more slip clutches or other means by
which to automatically disengage torque at appropriate times.

3. The device of claim 1 with a means by which to control electrical load
or otherwise control the flexibility of the device at hinge points.

4. The device of claim 1 whereby one or more transmissions or gearboxes
are added which increase the speed of one or more generators.

5. The device of claim 1 whereby one or more structural members are made
automatically adjustable in length resulting in improved energy
production.

6. The device of claim 1 whereby an interconnect system is included.

7. The device of claim 1 whereby one or more buoys are sufficiently
weighted resulting in useful torque during both upward and downward buoy
motions.

8. The device of claim 1 with a means by which to temporarily submerge
the device when environmental conditions are deemed too onerous.

9. A device for transforming the energy of water waves into useable
energy comprising two or more buoys, and structural members connecting
said buoys, at least three hinge points, whereby motions of said buoys
relative to one another generates torque, one or more shafts or other
means by which to transfer torque connected to one or more generators, a
means by which to ensure that one or more generator output currents flow
in a single useful direction despite the reversing of generator rotation,
and a means by which to control electrical load or otherwise control the
flexibility of the device at hinge points.

10. The device of claim 9 with one or more slip clutches or other means
by which to automatically disengage torque at appropriate times.

11. The device of claim 9 whereby one or more transmissions or gearboxes
are added which significantly increase the speed of one or more
generators.

12. The device of claim 9 whereby one or more structural members are made
automatically adjustable in length resulting in improved energy
production.

13. The device of claim 9 whereby an interconnect system is included.

14. The device of claim 9 whereby one or more buoys are sufficiently
weighted resulting in useful torque during both upward and downward buoy
motions.

15. The device of claim 9 with a means by which to temporarily submerge
the device when environmental conditions are deemed too onerous.

16. A device for transforming the energy of water waves into useable
energy comprising two or more buoys, and structural members connecting
said buoys, three or more hinge points that are elevated above mean water
level, whereby motions of said buoys relative to one another generates
torque, one or more shafts or other means by which to transfer torque
connected to one or more generators, a means by which to protect one or
more shaft locations from water penetration, a means by which to ensure
that one or more generator output currents flow in a single useful
direction despite the reversing of generator rotation, and a means by
which to control electrical load or otherwise control the flexibility of
the device at hinge points.

17. The device of claim 16 with one or more slip clutches or other means
by which to automatically disengage torque at appropriate times.

18. The device of claim 16 whereby one or more transmissions or gearboxes
are added which significantly increase the speed of one or more
generators.

19. The device of claim 16 whereby one or more structural members are
made automatically adjustable in length resulting in improved energy
production.

20. The device of claim 16 whereby an interconnect system is included.

21. The device of claim 16 whereby one or more buoys are sufficiently
weighted resulting in useful torque during both upward and downward buoy
motions.

22. The device of claim 16 with a means by which to temporarily submerge
the device when environmental conditions are deemed too onerous.

[0003] Populations grow exponentially, demand for energy is escalating,
and political tensions over hydrocarbons are increasing to say the least.
In light of these issues the U.S. Department of Energy continues to place
renewable energies as a focal point to their program.

[0004] When one looks across an open ocean and views the large rolling
waves the energy is glaringly obvious. Winds travel for hundreds of miles
and beautifully store and compact their energy into waves. The magnitude
of energy and density of energy in ocean waves is fairly easy to
comprehend. After all, only waves can pitch and roll ships weighing
thousands of tons.

[0005] To be cost-effective and viable, a wave energy device must be very
simple. It must also be strong to survive punishing ocean environments.
Last but not least, it must avoid sophisticated components and have any
critical components protected from the harsh oceanic environment.
Simplicity in design ensures low capital investment, low operating costs,
low maintenance costs, and low energy production costs. Ideally, a wave
energy system should be complete and demonstrate interconnectivity. An
individual device should not require individual mooring systems and
individual subsea electric cables to shore. Devices should float on the
water surface to extract maximum wave energy and either be capable of
withstanding storm events, be towed away when the largest of storms
arise, or temporarily sink below water level until storms pass.

[0006] Upon review of existing patents one will find that most have
addressed only a few of the challenging design requirements mentioned
above. Many wave energy patents that have avoided or eliminated the use
of one-way clutches have not sufficiently described how they work and how
they would actually be built. A patent specification must enable any
person skilled in the art or science to which the invention pertains to
make and use the same". Without sufficient descriptions a patent can be
deemed invalid. Without addressing all of the challenging design
requirements an wave energy device cannot cost-effectively and reliably
deliver power. The novel invention presented herein overcomes the above
challenges. Particular features not found in prior patent applications
make this invention fully viable, useful, and beneficial.

BRIEF SUMMARY OF THE INVENTION

[0007] The purpose of this invention is to efficiently and cost
effectively transform water wave energy into useful electrical energy
with little or no environmental impact. There are numerous advantages of
this particular invention in comparison with prior art.

[0008] Maximum available wave power, not partial available power, is
extracted by this device and it is extracted on both up and down strokes.
Torque arms, acting as levers, add mechanical advantage for power output.
The refined design ensures that capital costs will be very low and
reliability will be extremely high. Critical components are 100%
protected from oceanic spray keeping maintenance costs negligible. No
reversing gears are utilized and slightly higher gearing ratios are used
for significant benefits. The efficiency losses associated with reducing
gears is completely eliminated. Reversing gear systems have generators
that spin too slowly and are not of large enough diameter. Thus, these
generators become too heavy and expensive. Heavy generators inhibit a
wave energy device from harnessing energy because the device cannot
properly maintain rhythm or resonance with wave motions. Standard
gearboxes can and should be utilized instead of reversing gear systems
and such gearboxes can come from many suppliers at fairly low prices.

[0009] The use of one-way clutches in wave energy devices presents
additional efficiency losses and higher costs. It is better to simply
reduce the mass moment of inertia of the gearing and generator so that
both gearbox and generator can spin in both directions as waves rise and
fall. Multiple hinge points make the device stronger in rough seas and/or
quartering seas, enables system redundancy, and enables gearboxes and
generators with smaller diameters and lower mass moments of inertia. In
combination with reduced mass moments of inertia these wave energy
devices should have equipment that accommodates the changing direction of
a generator's current flow as waves change from up to down stroke. In
essence, sensors would recognize when waves change from up to down motion
or when a generator's current direction changes. At these moments the
electrical paths would be switched or flip-flopped so that a generator's
current is ultimately heading in the preferred direction. Modern
electrical equipment can have milli-second response times. In one
embodiment, as shown in FIG. 3, the electrical lines are switched at the
changing of wave strokes so that the outflow paths remain unchanged.

[0010] Buoys can be flooded and the device temporarily submerged below
water level. A system for interconnecting energy transformation devices
is included herein. Interconnectivity creates a truly complete system
that eliminates the need for many individual mooring lines, eliminates a
considerable amount of electrical cable, and it allows many of units to
be towed via a single tugboat. Towing of many units is desirable since
many units could potentially be installed or removed all at once. Mass
towing also enables production-line maintenance at shoreline.
Assembly-line maintenance at shoreline is far less expensive and safer
than maintenance or repair performed offshore. In essence, while many
other arrays are generating power just one array at a time can be brought
in for service.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0011]FIG. 1 is a plan and side view of a preferred embodiment of the
invention where reversing gears and one-way clutches have been eliminated
from the design.

[0012] FIG. 2 is a plan and side view of a preferred embodiment of the
invention where reversing gears, one-way clutches and gearboxes have been
eliminated from the design.

[0013] FIG. 3 is a drawing of a switch that could accommodate the changing
of wave up/down stroke.

[0014] FIG. 4 is an isometric view of a two buoy version of the device
with many hinge points.

[0015] FIG. 5 is a plan view of many devices connected together with an
interconnectivity and mooring system.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] The invention can be designed and scaled for any size waves. A
preferred embodiment would primarily be constructed of steel or other
suitable marine materials. Components of the device include two or more
buoys (1) connected by torque arms (2) whereby a pivoting motion is
permitted at hinge points (3) that have bushing or bearings. The buoy
movements generate torque which drive one or more gearboxes (4) which in
turns drives one or more generators (5) at higher speeds for electrical
output.

[0017] The complex transmission system described in U.S. Pat. No.
7,315,092 is too customized and expensive, reversing gears are not
necessary, and reversing gears present unnecessary efficiency losses.
Most importantly, the electrical load, or the amount a wave energy device
is trying to power, can be controlled such that the moment of inertia of
gearboxes and generators can be consumed before a wave reverses
direction. For example, electrical load can be electronically increased
just as a wave turns from going up to going downward which would stop the
gearboxes and generators. Thus, one-way clutches are not necessary. When
a gearbox with dual output shafts is used there can be two generators
which as shown at the bottom of the device depicted in FIG. 1. These two
generators are labelled as generator (6) and generator (7). This dual
generator configuration can inherently reduce the mass moment of inertia
of the system since two generators with smaller diameters can have less
moment of inertia than one generator of larger size and diameter. Another
problem associated with the transmission system described in U.S. Pat.
No. 7,315,092 is that it does not permit a high enough rotational speed
for the generators to work efficiently. As a result, the U.S. Pat. No.
7,315,092 has generators that are too large, too expensive, too heavy,
and they therefore inhibit the device's ability to move with the waves
and generate power. This is why gearboxes with higher gearing ratios have
been used in this invention.

[0018] Although it is desirable that wave energy devices be relatively
invisible on the horizon, corners/edges of arrays (many units linked
together) will likely be marked with traditional lighted buoys. This will
ensure that they are visible from ships at night and in fog.

[0019] All critical components are enclosed and protected since the buoys
(1) themselves function as protective shells. The only exposed moving
joints are the bushings/bearings (8) that are properly designed for
submersion in salt water. Common propeller shafts of ships have very
similar watertight bearings and seals. If desired, and since the torque
arms do not rotate in excessive angles, a sleeve (9) can be installed to
cover any bushings/bearings from salt water contact. This invention
deliberately raises the elevation of the pivot points (10) to above mean
waterline. Propeller shaft seals are designed to be used fully underwater
but leakage is far less likely with the pivot points, seals and
sleeves/boots elevated above waterline. Universal joints or flex joints
(11) may be used to ensure that only pure torque enters gearboxes.
Nylatron, plastic, or other pad materials (12) can be used at pivot
points to ensure the torque arms do not rub or contact the buoy.

[0020] In the preferred embodiment the buoys (1) are flattened but in
other embodiments the buoys could have a wide range of volumetric shapes.
Flattened buoys or buoys enable immediate response to wave motions. Buoys
are constructed of thick materials or deliberately weighted in this
embodiment such that they float at about mid level. Weights could be made
of concrete, other solid materials, or liquid materials. Buoyancy
provides an upward force while weight provides a downward force, both of
which generate useful torque. As a result, both upward and downward buoy
motions result in torque that ultimately drives generators (5). Splitting
this torque relatively evenly, vs. twice the torque on just up or down
strokes, reduces the cost of the drive train (gearboxes, generators,
etc). Without thick buoy plating or weights (13) the resistance of
generators (5) and gears would likely cause buoys to "stick" in an upward
position upon the first wave crest. At a minimum, the downward movement
of buoys would likely be delayed.

[0021] As mentioned previously, buoys are connected via torque arms (2).
Torque arms may have the capability of automatically extending or
retracting themselves via auto-lengthening mechanisms. Auto-lengthening
mechanisms can accommodate varying wavelengths as sea conditions change
on any given day. Arm length adjustability increases energy production
since distances between outer buoys can better match wavelengths on a
given day for optimized power output. In a preferred embodiment, one wave
energy device within a large array could measure wave heights and wave
periods. A computer program could then estimate average wavelengths from
the recorded data and instruct all torque arms within that array to
lengthen or shorten accordingly. In the preferred embodiment, the
auto-lengthening mechanisms are actuated electromechanically but they
could also be actuated via hydraulics or other means. Auto-lengthening
mechanisms, like the primary bearings, can be protected from saltwater
contact by waterproof sleeves.

[0022] With wave movements the motion of one buoy relative to the other
buoy or buoys creates extremely high torque. Very high torque is a result
of the large displacement of a buoy (1) coupled with the torque arm
lengths whether the arms are long or short. The high torque is next
directly transferred via the torque arms (2) to a shaft which rotates a
gearbox (4). Note that gears, chains and sprockets, or other means can
serve to transfer torque to one or more generators.

[0023] Similar to arrays of offshore wind turbines, electrical processing
equipment can take the electrical output of each generator, process and
combine it at a central electrical processing station, and send it to
shore via a single subsea cable, batteries, compressed air, or other
means. In a one embodiment a central electrical processing station is
enclosed within a windowless room and located on a barge near the center
of an array. The windowless room could be climate controlled and
dehumidified to better protect the equipment within the electrical
processing station. Alternatively, the central electrical processing
station could be located in a subsea pod.

[0024] Components of energy transformation devices that are exposed to the
elements, which include buoys and torque arms, can be structurally
designed for storm and hurricane forces. Offshore oil platforms have
similar pontoons and tubulars that are designed for such storms. Many
torque arms can be used and they can be laterally braced and/or trussed
(14) as well as vertically braced and/or trussed. In a preferred
embodiment, if excessively large waves were encountered, the gearbox
could automatically disengage via a clutch. Slip clutches (15) such as
those constructed of spring loaded frictional discs can be installed to
ensure that gearboxes and all remaining drive train machinery can never
be over-loaded. This disengagement feature permits wave energy devices to
accommodate excessively dynamic conditions without any damaging effects
to internal components.

[0025] In rough seas, wave energy devices would have a natural tendency to
collide with one another within their arrays. Note that any point on an
individual device will move through all six degrees of translation and
rotation within a wave cycle. Consequently, there is no single point on
an energy transformation device that can be "grabbed" or "held" rigidly
in an attempt to interconnect them. FIG. 5 shows flexible interconnection
lines (15) connected between devices with mooring lines (16) and anchors
(17) at the ends of arrays to keeps lines taught and all devices from
contacting one another. Items 15, 16, and 17 together create an
interconnect system.

[0026] Wave energy devices of this type with just two hinge points, as
described in U.S. Pat. No. 7,315,092, are not likely to be structurally
strong enough to handle waves coming from diagonal direction or
"quartering seas" as this is sometimes called. Devices with few hinge
points typically have fewer gearboxes and generators with much larger
mass moments of inertia. Many torque arms and hinge points are shown in
FIG. 4. Many hinge points not only makes the device stronger in rough
seas but it enables many gearboxes and generators, a lower total mass
moment of inertia in the machinery, system redundancy, and smaller gears
which can reduce costs. Smaller gearboxes and gears is just one way that
moment of inertia in the drive trains can be reduced which enables lower
energy losses. Rotation of generators directly and without gearboxes is
another way to reduce inherent energy losses and improve efficiency. With
the advent of slow rpm generators, annular generators (18), and direct
drive generators we can now eliminate gearboxes in wave energy devices.
Previous wave energy devices have not been able to successfully prove the
operation of, and thus patent, a truly viable wave energy device without
gearboxes. This is now possible when annular or direct drive generators
are used. An electronic means by which to control electrical load (19)
can be installed to reduce if not eliminate the mass moment of inertia of
machinery items between wave up and down strokes. Switches (20) or other
means by which to ensure that all current goes to grid in the desired
direction or fashion can also be added so that one-way clutches are not
necessary. In essence, these switches or other means make the reversing
of up/down wave direction irrelevant. A means by which to control
electrical load, or any other means by which to control the flexibility
of the device about hinge points, further enables the device to stay in
sync with wave motions which can improve if not optimize power output.

[0027] Patent applications must sufficiently describe a system for the
patent to valid. Furthermore, inventions are novel, beneficial, and
patentable when they greatly simplify existing inventions and improve
efficiency. Adding an item to an existing invention could be considered
infringement. Patent laws state that subtracting items, however, can
result in new patents. In summary, inventions that result in fewer
components, simplified systems, and higher efficiencies are patentable.
This is the case in this invention.